refactor(demo): change demo route to error-window

Author: ngonzalezpazFC

src/test/java/com/flowingcode/vaadin/addons/errorwindow/ErrorwindowDemoView.java

@@ -11,7 +11,7 @@
 import java.awt.TextField;
 
 @SuppressWarnings("serial")
-@Route(value = "errorwindow", layout = DemoLayout.class)
+@Route(value = "error-window", layout = DemoLayout.class)
 public class ErrorwindowDemoView extends VerticalLayout {
 
 	public ErrorwindowDemoView() {